Insulators

An insight into Design, Development & Testing of insulation piercing Connectors for LV Application.

Introduction:

  • Designed  for Indoor and Outdoor Applications.
  • Non-tension tap and  splice applications.
  • Used in insulated Secondary distribution lines.

Details regarding the material:

Stainless steel

  • Austenite stainless steel confirming UNI 6900
  • C (0.08), Mn (2.00), Si (1.00),P (0.045), Ni (8.00/12.00),Cr (18.00/20.00)

Mild Steel:

C (0.15-0.25), Mn (0.60-0.90), Si (0.15-0.35), P(0.03)

Tinned Copper:

  • Have Brinnel hardness>100
  • Copper alloy-Taken from the list of UNI2012

Glass Reinforced Plastic:

  • Withstand thermal mechanical solicitation
  • Water absorbing (UNI ISO62 or ASTMD 570 )measured on samples dim 50x50x3, 2mm was lower than 0.2% after 24 hours of water immersion at and lower than 1% under saturation condition.
  • Internal sliding module on samples dim 120x20x6mm, with 10N/sqmm bending moment, after 96hours was =6500N/sqmm at 80c.

Insulating Material:

  • During service operations within of temperature range of -30.c/+80.c
  • During short time current condition with max cable temperature of 250.c
  • Resistant to UV rays.

Tests Performed on the IPC:

The IPC undergoes thorough testing before being certified suitable use………

  • Control of the building and execution characteristics.
  • Dimensional control.
  • Materials controls.
  • Assembly and removal tests.
  • Verification of the electrick  and mechanic characterstics of clamping.
  • Verification of the residual break load of the main cable and of the sliding load of the derived cable.
  • Test of the characterization of the organic materials.
  • Long duration ageing tests for the organic materials.
  • Dielectric withstand test.
  • Percussion test.
  • Thermal cycles and high intensity currents  tests in the air.
  • Protection degree verification
  • Verification of the dropping points of the sealing pastes and greases.

Control of the building and execution characteristics :

  • Installation is possible with aerial cables already sagged  as per specs.
  • Components of connector should be so designed that the assembly will not require special training and connections should not be prone to mistake on account of errors or lack of skill of lineman.
  • All parts are captive and assembling by singel tool with dedicated screw accessory.
  • It is possibe to insert cables into cannector easily and without fully unscrewing  bolts and parts.
  • Therefore it should be verified, by visual test, that the cannectors are free from any constration defects or supreficial irregularities.
  • All external parts are designed to avoid damages on cable cores.
  • Surface does not have sharp edge.

Dimensional control & Materials control:

  • All Dimensions meet the drawing dimensions with tolerances.
  • The materials used for making IPC undergo proper materials tests for
  • Metallic material —–1)Steel, 2) Tinned Copper
  • Insulating Material
  • Thermoplastic used

Assembly and removal tests:

  • The assembly is easy.
  • The cores of the cable do not get damaged
  • After the connectores  assembly it is verified that the cores of the cables are not damaged.
  • The disassembly of the cannector is easy to perform.
  • Finally to check visually the contact marks left on the cable. This test should reveal a regular and uniform

Verification of the electric and mechanic characterstics of clamping:

Connector assembly

  • Divide the assembled cables -connectors in two different groups and respectively be conditioned , for at least 2 hours, at the temperature of -10±1 °c and of 50±1 °c.
  • Afterwards the assembled cable cannectors should be taken out from the conditioning  room and within max 2 minutes the connections should be performed, applying on the bolt the tightening torque.shear head of the bolt should break below the max value 18Nm torque. 

Verification of the electric resistance of the connectores.

Verification of the mechanical resistance of the connectors.

Verification of the residual break load of the main cable and of the sliding load of the derived cable:

  • Connectors assembly.
  • Test with high intensity currents.
  • Verification of the residual break load of the main cable.
  • Verification of the slipping load of the derived cable.

To know more details about INSULATOR click here…Insulator

 

 

 

 

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

%d bloggers like this: